The present invention is directed to a hearing aid device comprising a housing containing electrical components, such as a microphone, amplifier, earphone, power source, on/off switch, control elements or the like.
German OS 36 23 906 discloses a hearing aid whose components in the inside of the hearing aid housing are contacted with at least one printed circuit board. In order to be able to avoid soldering the components to the printed circuit board, the printed circuit board itself is constructed at least partially resiliently, whereby the components to be fastened are releasably held in a contacting fashion between the resilient parts of the printed circuit board and a cooperating member. An elastic contact pillow composed of an elastic silicone mat with parallel through metal threads embedded therein can thereby be provided between the printed circuit board and the cooperating member so that the upper ends of the metal threads touch the contact legs of the component and the lower ends of the metal threads will touch the interconnects of the printed circuit board when the pillow is compressed. Contact is, thus, produced between the component and the printed circuit board.
In order to simplify the wiring of electrical components in a hearing aid device, German Gebrauchsmuster G 88 06 161 discloses at least one part of the wiring which is arranged on the inside of the housing shell. A cable tree with terminals can thereby be laid on the inside of the housing shell or at least sections of the inside can comprise an electrically conductive coating.
Copending U.S. patent application Ser. No. 07/808,534, which issued as U.S. Pat. No. 5,265,168 on Nov. 23, 1993 and which claims priority from European Patent Application 90 124 629.8, is directed to a hearing aid having at least one microphone, an amplifier means, an earphone and a current source, as well as having components fashioned as controls, switches or regulating elements that are contacted with at least one printed circuit board on the inside of the hearing aid housing. An anisotropic, electrically conductive, plate-shaped, foil-shaped or mat-shaped member composed of an electrically insulating matrix material having a plurality of electrically conductive fibers that are aligned perpendicular to the plane of the plate, foil or mat and are uniformly distributed in the mat is arranged in between the interconnects of the printed circuit board and the contacts of the components that can be secured to the printed circuit board. The controls and/or potentiometers and/or switches are arranged at the printed circuit board upon employment of the anisotropic member as a contact element. As a result of this arrangement, the electrical connections between the components are intended to be assembly-friendlier and capable of being produced without soldering processes, whereby the components are secured in an easily interchangeable way and the structure of the switches and potentiometers themselves are simplified. U.S. Pat. No. 4,199,637, which corresponds to German B 26 52 683, discloses the anisotropic, electrically conductive member that is provided.
In hearing aids, finally, the employment of sensor pins is known for controlling the volume via a sensor circuit (see, for example WO 87/06422, which corresponds to European Published Application 0 241 594). U.S. Pat. No. 4,955,729, which claims priority from several German Applications including German 37 16 162, discloses a hearing aid which has sensor switches which will respond to condition changes so that when putting an in-the-ear hearing aid on or taking it off, the sensors will trigger the automatic turning on and turning off of the hearing aid. Other possible sensor changes are those such as temperature, light, moisture, electrically conductivity of the skin surface.